This invention relates to coated seeds and to a method for coating seeds.
In the Technology Newsletter appearing on page 33 of Chemical Week, dated Aug. 12, 1981, it is pointed out that researchers from the Department of Agriculture have found that a coating of polyethylene glycol on soybean, pea and other legume seeds improves germination and early growth. This is supported by the statement that Lowell W. Woodstock and Kar-Ling J. Tao, reporting in Physiologia Plantarum, say that seed growth depends in part on the seed's ability to withstand the rapid uptake of water immediately after p)anting. According to this item, because polyethylene glycol molecules are larger than water molecules, the chemical slows this water uptake by blocking the passage of water through the membrane to the critical growth axis of the seed, giving the seed membrane time to repair damage and reduce the leakage of enzymes, nucleotides, amino acids and other cell constituents that regulate the seed's life processes. The Chemical Week item goes on to report that two researchers from Boyce Thompson Institute (Ithaca, N.Y.) have also shown that soybean seeds coated with polyethylene glycol and gum arabic exhibit substantial protection against injury from chilling.
Because of the vagaries of weather, it is not possible to control the amount of rainfall upon the open fields. As a result, when a heavy rain follows the planting of soybean and other legume seeds which have been coated with a polyoxyethylene glycol polymer, the coating disappears rapidly due to its high rate of solubility in water. This leaves the seeds without the protective coating and thus susceptible to the many dangers due to chilling and/or high moisture content of the ground surrounding the seed. Accordingly, it is a purpose of this invention to provide coated seeds which may be planted early either before or during the spring rainy season which are not as susceptible to the problems presented by said spring rains.
______________________________________ U.S. Patents of Interest U.S. Pat. No. Issued Inventor(s) Assignee ______________________________________ 3,803,761 4/16/74 Watts et al Dow 3,947,996 4/6/76 Watts Dow 3,698,133 10/17/72 Schreiber Canadian Patents & Development Ltd. 2,999,336 9/12/61 Cescas Compagnie Nord-Africaine de L'Hyperphosphate 4,377,054 3/22/83 Howe et al Monsanto ______________________________________